Selenium is considered to be an element essential for the proper functioning of animal and human organisms. Its most important functions include anticancerogenic activity and beneficial effects on the human circulatory system, as well as its role during the perinatal period in animals. This article discusses a significant role selenium plays in animal organisms, the soil content of this element in soils, and a prospect for Se enrichment in plants to levels covering the dietary needs of animals. The incidence of selenium deficiency in animals can be reduced by enriching fodder with supplements containing selenium in mineral compounds, which are much less assimilated by living organisms than its organic forms. The paper also provides information on the content and bioavailability of selenium in Polish soils and presents the average concentrations of this element in different species of plants. While the methods of introducing selenium into the soil-plant-animal-human food chain have been extensively studied during the recent years, the practice of fertilizing plants with this element is still less known. The basic source of selenium for plants is soil, yet most of the soils in Poland are poor in selenium. It has been demonstrated that the application of 5 to 10 g ha-1 Se in the cultivation of cereals, meadows and pastures may increase its content in plants to the level covering the needs of animals for this element. The effectiveness of Se enrichment in plants to a level safe in animal nutrition may depend not only on the dose or chemical form of selenium applied, but also on the species and varietal properties of plants, the time of application and the application method itself. Due to a small difference between the optimal and toxic content, plant fertilization with selenium should be preceded by a study on its content in soil, as well as the ability of plants to accumulate this element.

24.3.2019